Field of the Invention
The present invention relates to a driving apparatus and an optical apparatus using the driving apparatus, and more particularly, to a driving apparatus and an optical apparatus using the driving apparatus, which are suitable for lens drive in an image pickup apparatus.
Description of the Related Art
In general, a driving apparatus is mounted to a lens configured to take moving images for professional use. The driving apparatus is capable of electrically driving a variety of operation of the lens in order to smoothly take a shot at a fixed angle of view or with zooming at ultra-low speed, which is difficult to achieve by manual operation. However, in a case where the lens is electrically driven to perform zooming or focusing while taking the moving images, vibration due to a motor mounted on the driving apparatus as well as resonance with a lens barrel-forming member that may be caused by the vibration and noise resulting from the vibration is recorded.
Therefore, the driving apparatus of the lens is increasingly required to have a structure reduced in vibration and noise. As a structure configured to reduce vibration and noise of the driving apparatus, it is known to interpose an elastic member (damping washer) between a motor housing configured to hold (enclose) a motor and a fixing member configured to fix the motor housing (Japanese Patent Application Laid-Open No. 2013-105094). Vibration and noise of the motor can be thus reduced.
In connection with the above-mentioned related art, the hardness of the elastic member may be reduced to achieve further reduction of vibration and noise of the apparatus. According to this method, however, the motor housing mounted on the driving apparatus is spaced apart from the lens due to force that may be generated at a tooth tip of a gear mounted between the lens and the driving apparatus. The gear between the lens and the driving apparatus is thus separated to be unmeshed, thus resulting in occurrence of a “tooth skipping” phenomenon in which the gear of the motor mounted on the driving apparatus rotates in the unmeshed state. Occurrence of tooth skipping not only causes wear of teeth in the meshing portion but also rotates the gear in the unmeshed state, thus resulting in occurrence of vibration and noise phenomena derived therefrom.